Many methods and processes in the field of life sciences, molecular biology, process chemistry and organic chemistry comprise one or more steps, typically separation or extraction steps where two or more phases, such as organic (non-aqueous) and aqueous phase, or hydrophilic and hydrophobic phase, are required to be separated. It is also often desirable to separate solid or semi-solid materials, such as particles or aggregates from a suspension or mixture to obtain a clear liquid or a liquid containing a desired compound or compounds dissolved therein, which may be isolated from said liquid.
In molecular biology, extraction procedures are typically associated to DNA purification methods. It is often important to obtain pure samples of plasmids, nuclear DNA and RNA from samples, in assaying for genes which express particular proteins, to determine whether or not a particular sample of cell has been transfected by a foreign gene and so forth. A widely used method for extracting DNA involves differentiated solvation of the DNA and the non-DNA material, using phenol and chloroform. The DNA containing sample, typically after several preparative steps, is mixed with an organic solvent, usually phenol or a mixture of phenol and chloroform. Proteins denaturate and enter the organic phase (phenol) or precipitate at the interphase between the organic phase and aqueous phase. The aqueous phase contains the DNA. Mixing of the aqueous phase with alcohol results in the precipitation of the DNA, which then can be spooled. Standard protocols for the separation of the phases require aspiration of the aqueous DNA containing solvent. However, both solvents phenol and chloroform are regarded as potentially carcinogenic compounds. Pouring of the material from the second solvent is not acceptable because the barrier between phenol and chloroform is not very stable and contamination of phases is inevitable. At the interphase between the layers, it often becomes difficult to separate the DNA. Frequently poor phase separation and cloudy interphase between the two phases is noticed, which typically encumbers the removal of the desired phase.
Some phase lock agents have been proposed for preventing protein interphase contamination, for easing the phase separation and forming a clearer interphase between the two phase layers.
U.S. Pat. No. 5,106,966 suggests the use of a polyester gel polymer for easing phase separation and purification of DNA from a biological sample.
U.S. Pat. No. 5,175,271 relates to the use of gels based on silica gel polymers for the same purpose as above.
There is a need for new, rapid and efficient separation agent and phase lock materials to be used particularly for phase separation and for separation of solid material from liquid, suitable for applications in molecular biology, process chemistry, life sciences and organic chemistry.